This invention relates to pipe couplings and, more particularly, to pipe couplings of the quick-connect type for thermoplastic pipe wherein connection is effected automatically by axial movement of a pipe connector end into a chamber.
In establishing flow lines, it is often necessary to couple together the ends of a pair of pipe sections on location. Mechanical couplings which employ bolts or clamps are cumbersome and time-consuming to operate and may require the use of special tools. Couplings have been proposed in which connection is automatically effected by axially merging the connector ends together as demonstrated, for example, in U.S. Pat. Nos. 921,691, issued to Friday on May 18, 1909; 2,452,219, issued to Bergvall et al on Oct. 26, 1948; and 3,809,412, issued to Glover on May 7, 1974. As these patents demonstrate, the couplings can involve insertion of one connector end into a socket of the other connector end, or inserting both connector ends into a separate sleeve. Connection is automatically and quickly effected by the entry of a projection in one part within a recess of another part to prevent separation of the connector ends. While couplings of this nature enable connections to be made rapidly, it is often necessary that the connection be highly secure and leak-proof. Accomplishing this without diminishing the ease and rapidity of the connecting operation can present numerous difficulties, especially with regard to flow lines which are to conduct fluids under substantial pressure.
It can also be prohibitively expensive to form the ends of flow lines of the intricate shape required of many quick-connect couplings.
An easily manipulable coupling arrangement of the quick-connect type which provides a secure, leak-proof connection would be ideally suited in instances where flow lines are established in the field and are situated where subsequent access is inconvenient. Plastic drainage pipelines which are to be buried constitute one special area of utility for such couplings.
It is, therefore, an object of the present invention to obviate or minimize problems of the type discussed above.
It is another object of the present invention to provide a novel pipe coupling.
It is a further object of the present invention to provide a novel quick-connect coupling assembly which provides a secure and leak-proof connection.
It is yet another object of the present invention to provide a novel and inexpensive quick-connect coupling which is easily adapted to conventional pipe sections, particularly those of the thermoplastic variety.